Biochemical changes following succinylcholine administration after pretreatment with rocuronium at different intervals.

OBJECTIVE To evaluate the biochemical changes associated with succinylcholine administration after pretreatment with rocuronium at different time intervals. METHOD The prospective, randomised, single-blinded study was conducted at the Combined Military Hospital, Rawalpindi, from January to May 2010. Ninety male, aged 18-60 years, American Society of Anaesthesiology I or II patients undergoing elective inguinal herniotomy or external haemorrhoidectomy were included. The patients were randomly divided into three equal groups. Group A received a normal saline 5 ml as placebo 1 minute before succinylcholine; Group B received rocuronium 0.06 mg/kg 1 intravenously minute before succinylcholine, while Group C received intravenous injection of rocuronium 0.06 mg/kg 5 minute before succinylcholine. Venous blood samples for creatinine phosphokinase, lactate dehydrogenase and myoglobin plasma concentrations were obtained at 0, 30 minutes, 6 hours and 24 hours after succinylcholine administration. RESULTS Mean serum creatinine phosphokinase and myoglobin concentrations were significantly decreased in Groups B and C compared to Group A at 30 minutes and 24 hours (p < 0.05). However, no significant difference in the enzyme levels at any time interval was observed among the rocuronium groups. There was a significant rise in lactate dehydrogenase concentrations at 6 hours and 24 hours in Group A compared to Groups B and C (p < 0.05). CONCLUSION Pretreatment with rocuronium effectively reduces the biochemical changes associated with succinylcholine-induced muscle fasciculations. However, whether it is given 1 minute or 5 minutes before succinylcholine does not make much difference.